Rail wheel attachment for a vehicle

ABSTRACT

A rail wheel attachment for a road vehicle allowing the vehicle to travel on the rails of a railway track. The attachment has a mounting unit for mounting the attachment to the vehicle and a rail unit underneath the mounting unit. The mounting unit has a vertical moving unit mounted on each end of the unit. The rail unit has an axle slidably mounted thereon with rail wheels at its ends. Transverse moving elements on the rail unit move the axle transverse to the vehicle. The vertical moving units connect to the rail unit to raise or lower it relative to the mounting unit along a straight line. The vertical moving units cushion the movement of the rail unit relative to the mounting unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of Canadian application no. 2,474,189, entitled “A Rail Wheel Attachment For A Vehicle”, filed Aug. 6, 2004, and which is incorporated herein by reference.

FIELD OF THE INVENTION

This invention is directed toward a rail wheel attachment for road vehicles. The invention is also directed toward a rail unit for use with a rail wheel attachment; toward a mounting unit for use with a rail wheel attachment and toward a moving means for use with the rail wheel attachment. The invention is also directed to a method for using the rail wheel attachment.

DESCRIPTION OF THE RELATED ART

It is known to run road vehicles on the rails of railway tracks. The road vehicles are provided with rail wheel attachments having rail wheels that can be lowered from a raised, road travel position to a lowered, rail engaging position. To run the road vehicle on rails, the vehicle is normally positioned over a railway track at a road crossing with the rail wheels over the track. The rail wheels are then lowered onto the rails of the track. The rail wheels can be lowered enough to raise the road wheels of the vehicle off the track. A motor for the rail wheels then drives the vehicle on the track. Alternatively, the rail wheels can be lowered just enough to place the road wheels fully on the rails with nearly all the weight of the vehicle carried by the road wheels. The road wheels drive the vehicle on the track. These known rail wheel attachments include a design which raises and lowers the rail wheels by swinging them about a pivot axis. The attachments need room to swing the wheels and therefore require extra space which can make installation of the attachment to a vehicle a problem. Other known rail wheel attachments have means for raising or lowering the wheels along a vertical line. The raising or lowering means can comprise a scissors mechanism which is quite complicated.

It can also be difficult to align the rail wheels with the track and a busy roadway can have traffic tied up while alignment of the vehicle is proceeding. To speed up the mounting of the vehicle on the track it has been proposed to mount the rail wheels in such a manner that the vehicle can be moved sidewise to bring the tires of the vehicle over the rails. In the prior art in which such devices are shown, none of the weight of the vehicle is removed or lifted from the tires before the vehicle is dragged sidewise. Under such conditions, dragging the road wheels into place onto the rails is hard on the tires. Example of such devices are shown in U.S. Pat. Nos. 4,583,465 and 5,660,115. In addition to damaging the tires the attachments must be strong for the friction forces that have to be overcome. To be strong enough, the attachments are usually quite bulky and thus heavy. In addition, problems arise when they are to be mounted at the front of the vehicle. Many large trucks have the front engine hood pivoted at the front of the truck and in order for the hood to fully open, the space in front and just below the hood must be clear. Often there is no room for bulky attachments. Also, on large trucks with a long wheel base, the spacing between the front and rear rail wheel attachments may be too great to safely go around curves on a track without derailing. The front attachment is therefore mounted behind the cab to reduce the wheelbase between the rail wheels. In this position, a compact attachment is again desirable.

SUMMARY OF THE INVENTION

It is a purpose of the present invention to provide a rail wheel attachment for vehicles which is compact in size and light in weight compared to known attachments. It is another purpose of the present invention to provide a rail wheel attachment which can move the rail wheels between an operative and inoperative position in a straight, generally vertical line and which can also easily and simply move the rail wheels laterally with respect to the vehicle they are mounted on. It is a further purpose of the present invention to provide a compact and lightweight mounting unit for a rail wheel attachment carrying vertical moving means for moving a rail unit, carrying rail wheels, in a straight vertical line. It is yet another purpose of the present invention to provide a compact and light weight rail unit, carrying rail wheels, for a rail wheel attachment that has transverse moving means for moving the rail wheels laterally. It is a further purpose of the present invention to provide a rail wheel attachment that can be used on large vehicles. It is a further purpose of the present invention to provide a compact vertical moving means for a rail wheel attachment for moving the rail unit in a straight vertical line. It is another purpose of the present invention to provide a rail wheel attachment with suspension means for cushioning the movement of the rail wheels relative to the vehicle when operational. It is yet another purpose of the present invention to provide a rail wheel attachment that allows the operator to quickly convert a road vehicle to a rail track vehicle and back again. It is another purpose of the present invention to provide a method for placing a road vehicle on or off rails using the rail wheel attachment of the present invention which allows the vehicle to more easily be moved onto and off the rails with less wear on the tires and less stress on the vehicle frame and components.

In accordance with the present invention, a rail wheel attachment is provided having a mounting unit and a rail unit beneath it. The mounting unit has a mounting frame, which is used to attach the attachment to a road vehicle, and vertical moving means. The rail unit has an axle with rail wheels at each end of the axle. The vertical moving means are connected between the mounting frame and the axle for moving the rail unit up or down in a straight, generally upright, line. Thus the rail unit can be raised or lowered in a very compact space. The vertical moving means preferably include suspension means for cushioning the movement between the rail unit and the mounting unit. Preferably, the rail unit has an axle frame supporting the axle. The vertical moving means in this case are connected between the mounting frame and the axle frame. Transverse moving means are provided on the rail unit connected between the axle frame and the axle for moving the axle relative to the axle frame. The axle is moved transverse to the longitudinal axis of the vehicle the attachment is mounted on.

The invention also covers the mounting unit per se consisting of the mounting frame and the vertical moving means carried by the mounting frame at its ends. The mounting unit can be sold alone and the buyer could mount any rail unit on it.

The invention further covers a rail unit per se, the rail unit consisting of an axle frame, an axle slidably mounted on the axle frame and transverse moving means connected between the axle frame and axle. The transverse moving means can be located outside the axle, but to make the unit even more compact, the transverse moving means can be located inside the axle means. Again, the rail unit could be sold as a separate unit for attachment to existing rail wheel attachments. Some modification of the existing rail wheel attachments may be necessary.

The invention also covers the vertical moving means for moving the rail unit relative to the mounting unit. The moving means include mounting means for mounting the moving means in an upright position on the mounting unit. The moving means also includes the suspension means and has the suspension means slidably mounted within the mounting means, the suspension means connected between the mounting unit and the and the rail unit. The moving means also has a moving unit slidably mounted within the suspension means and connected between the rail unit and the mounting unit for moving the rail unit up or down relative to the mounting unit.

The rail wheel attachment is mounted on a vehicle by means of the mounting frame in the mounting unit. During normal use of the vehicle, supported on its vehicle tires, the rail unit is raised relative to the mounting frame, by the vertical moving means, thus lifting the rail wheels on the rail unit up, out of the way, during normal travel of the vehicle on the highway. When the vehicle is to travel on the rails of a railway track, the vehicle is parked over the rails with the tires on the rails. The rail unit is then lowered by the vertical moving means in a straight vertical line to place the railway wheels on the rails. The tires can still contact the rails however to drive the vehicle on the tracks guided by the rail wheels on the rails. Alternatively, the rail wheels can be lowered a sufficient distance to raise the vehicle tires off the rails, the vehicle then driven by small motors on the rail units rotating the rail wheels. The vehicle is quickly converted to a road vehicle at a railway crossing by lifting the rail unit in a straight vertical line off the tracks so the whole weight of the vehicle is on the vehicle tires.

To mount the vehicle on a track when equipped with a rail unit on the attachment having the transverse moving means, the vehicle is parked parallel with the track and with the raised rail wheels over or close to alignment with the rails. If the rail wheels can be located directly over the rails, the rail wheels are moved directly down onto the tracks. However if the wheels are to one side of the rails, the transverse moving means moves the wheels until they are over the track and then they are lowered by the vertical moving means. The vertical moving means move the rail wheels down a sufficient distance to have them carry a substantial portion of the vehicle weight. Once the wheels are on the rails, the transverse moving means are moved again to move the vehicle transversely to position the vehicle tires over the tracks. The tires are dragged laterally during this movement, but the wear and tear on the tires during this operation is not as bad as before since a substantial portion of the vehicle weight is now supported by the rail wheels. The rail wheel attachment is adjustably mounted onto the vehicle so that the distance the rail wheels move down relative to the vehicle tires can be predetermined to provide the desired amount of weight transfer to the rail wheels.

The invention is particularly directed toward a rail wheel attachment for a road vehicle allowing the road vehicle to travel on rails. The attachment has a mounting unit and a rail unit underneath it. The mounting unit has a mounting frame; and vertical moving means mounted on the ends of the mounting frame. The vertical moving means are connected to the ends of the rail unit to raise or lower the rail unit relative to the mounting unit along a straight line. The vertical moving means have suspension means for cushioning the movement of the rail unit relative to the mounting unit.

The invention is also directed toward a mounting unit for use in a rail wheel attachment, the mounting unit having a mounting frame and vertical moving means mounted at the ends of the mounting frame. The vertical moving means have suspension means for cushioning the movement of the rail unit relative to the mounting unit.

The invention is further directed toward a rail unit for use in a rail wheel attachment, the rail unit having an axle frame. An axle is slidably mounted on the axle frame with wheels at the ends of the axle. The rail unit has transverse moving means on the axle frame connected to the axle to move the axle relative to the axle frame.

The invention is also directed toward a vertical moving means for use in a rail wheel attachment. The vertical moving means connects a mounting frame in the attachment to a rail unit below the mounting frame. The vertical moving means has mounting means for fastening to the mounting frame; suspension means slidably mounted for a limited extent in the mounting means and a vertical moving unit slidably mounted within the suspension means, the moving unit connected at its top to the suspension means and at its bottom to the rail unit.

The invention is further directed toward a method for using the rail wheel attachment comprising positioning the vehicle adjacent a rail track with the vehicle wheels adjacent the rails of the track; moving the rail wheels transversely to place them over the rails; lowering the rail unit to place the rail wheels on the rails while a substantial portion of the weight of the vehicle is transferred onto the rail wheels; and then moving the vehicle laterally to drag the vehicle wheels onto the rails.

BRIEF DESCRIPTION OF THE FIGURED IN THE DRAWINGS

FIG. 1 is a front elevation view, partly broken away, of one embodiment of the rail wheel attachment in a raised, inoperative position;

FIG. 2 is a side elevation view of the rail wheel attachment with the rail wheel removed;

FIG. 3 is a cross-section view of the vertical moving means with the cylinder retracted;

FIG. 3A is a cross-section view of the vertical moving means with the cylinder partially extended;

FIG. 4 is a cross-section view with the cylinder fully extended and with springs compressed;

FIG. 5 is front view of another embodiment of a rail unit;

FIG. 6 is a cross-section view along line 66 in FIG. 5;

FIG. 7 is a cross-section view of the rail unit along line 7-7 in FIG. 5;

FIG. 8 is a partial detail view, in cross-section, of the transverse moving means on the rail unit with the rail wheels centered;

FIG. 9 is a partial detail view, in cross-section, of the transverse moving means with the rail wheels offset;

FIG. 10 is a partial front elevation view of another embodiment of the rail unit;

FIG. 11 is a cross-section view taken along line 11-11 in FIG. 10;

FIG. 12 is a cross-section view taken along line 12-12 in FIG. 10;

FIG. 13 is a cross-section view taken along line 13-13 in FIG. 10;

FIG. 14 is a partial front elevation view of a swinging moving means;

FIG. 15 is across-section view taken along line 15-15 in FIG. 14;

FIG. 16 is a side view of the moving means in FIG. 14 in an operative, lowered, position; and

FIG. 17 is a side view of the moving means in FIG. 14 in an inoperative, raised, position.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

The rail wheel attachment 1, as shown in FIGS. 1 and 2, has a mounting unit 3 and a rail unit 5 underneath it. The mounting unit 3 has a mounting frame 7 adapted to be attached to a vehicle frame. The mounting unit 3 also carries vertical moving means 9 on each side of the mounting frame 7. The vertical moving means 9 are connected to the rail unit 5 and vertically move the rail unit 5 in a straight line relative to the mounting frame 7. The rail unit 5, in the embodiment shown, has an axle 11 with a rail wheel 13 at each end. The axle 11 is a hollow tubular member with a spindle (not shown) fixed at each end on which the wheel 13 rotates.

In more detail, the mounting frame 7 of the mounting unit 3 has vertical side plates 15, 17 joined by horizontal, bottom frame members 19. The mounting frame 7 is adapted to be mounted on the pair of laterally spaced-apart main beams A, B of the vehicle frame which beams extend longitudinally. The mounting frame 7 is mounted by its side plates 15, 17, one side plate 15 adjacent the outside of one beam A and the other side plate 17 adjacent the outside of the other beam B. Nuts 25, and bolts 27 passing through slots 28 in the side plates 15, 17, connect the side plates 15, 17 to the beams A, B. The bottom frame members 19 extend underneath and across the beams A, B. The height of the side plates 15, 17, and thus of the mounting frame 7, can be adjusted relative to the vehicle frame beams A, B when first installed using the slots 28 and shims (not shown) if required. While the mounting frame 7 has been shown and described with the side plates 15, 17 mounted on the outside of the main beams A, B of the vehicle, they could also be mounted on the inside of the beams. Also, while the horizontal frame members 19, joining the side plates 15, 17, have been shown and described as being located under the beams A, B they could also be located on top of the beams or in the middle of the beams in the embodiment where the side plates are located on the inside of the beams or not used at all if the vehicle frame has enough strength itself via cross members.

The mounting frame 7, as shown in FIGS. 1 to 4, has top and bottom support plates 33, 35 fixed to the top and bottom of the side plates 15, 17 and extending outwardly therefrom. The vertical moving means 9 has mounting means 36 for mounting the moving means on the support plates 33, 35 on each side plate 15, 17. The mounting means 36 comprises an outer mounting tube 37 which passes between the support plates 33, 35, the mounting tube 37 fixed to the support plates 33, 35 and the side plates 15, 17. The mounting tube 37 extends just above and just below the support plates 33, 35 and is open at both ends. The mounting tube 37 is positioned on the side plates 15, 17 to be in a generally upright position when the mounting frame 7 is connected to a vehicle.

The vertical moving means 9 includes suspension means 39. The suspension means 39 has an inner guide tube 41 and a pair of spring members 43. The inner guide tube 41 slides snugly within the outer mounting tube 37 and extends downwardly therefrom with its open bottom end 45 below the bottom of the outer mounting tube 37. The top of the inner guide tube 41, above the top of the outer mounting tube 37, is closed by a cover 47 as shown in FIG. 3. The bottom portion of the inner guide tube 41, below the outer mounting tube, carries a spring mounting plate 49, the spring mounting plate extending to either side of the inner guide tube 41. The pair of spring members 43 are mounted between the bottom support plate 35 on the outer mounting tube 37 and the spring mounting plate 49, one on each side of the inner guide tube 41, as shown in FIGS. 1 and 2. The spring members 43 will cushion movement of the rail unit 5 relative to the mounting unit 3 and thus relative to the vehicle.

Vertical moving units 50 are mounted within each vertical moving means 9. The vertical moving units 50 preferably are hydraulic and have a hydraulic cylinder 51 slidably mounted within the inner guide tube 41. The cylinder 51 has closed, upper and lower ends 53, 55. A fixed piston head 59 and a piston rod 61 is located within the cylinder 51 with the piston head 59 adjacent the lower end 45 of the inner guide tube 41. A piston rod 61 passes from the piston head 59 through the upper end 53 of the cylinder 51 and through the cover 47 of the inner guide tube 41. The top of the piston rod 61 passes through a stop plate 63 sitting on top of cover 47. A nut 65 threaded onto the top of the piston rod 61 prevents it from dropping through the stop plate 63 and cover 47. A stop member 67 is fixed on the piston rod 61 just beneath the cover 47. The stop member 67, together with the nut 65, lock the piston rod 61 in place relative to the cover 47. The stop plate 63 abuts on the open top end of the outer mounting tube 37 preventing the inner guide tube 41 from dropping through the outer mounting tube 37. The cylinder 51 is movable in and out of the inner guide tube 41 moving relative to the piston head 59 which remains fixed as shown in FIG. 4. The lower end 55 of the cylinder 51 is fixed to the axle 11 of the rail unit 5 as will be described.

The piston rod 61 is hollow allowing hydraulic oil, in the case of hydraulic actuators, to pass between the top end of the rod 61 and the cylinder 51 above the piston head 59 through a hole (not shown) in the wall of the hollow rod. The bottom closed end 55 of the cylinder 51 also has a hole (not shown) therein allowing oil to pass into or out of the cylinder 51 below the piston head 59.

The axle 11 on the rail unit 5 has a mounting pad 71 on the top of the axle near each wheel 13. Each pad 71 has a pair of brackets 73. A tubular member 75 on the bottom 55 of the cylinder 51 fits snugly within the brackets 73. A pin 77 passes through aligned holes 79 in the brackets 73 and the tubular member 75 to connect the rail unit 5 to the vertical moving means 9 and thus to the mounting unit 3.

In use, the mounting unit 3 of the railway wheel attachment 1 is mounted on the vehicle by fixing the side plates 15, 17 of the mounting frame 7 to the beams A, B of the vehicle frame. The axle 11 is centered with respect to the mounting frame 7 and the vertical moving units 50 are retracted with the cylinders 51 raised, as shown in FIG. 3. Thus the rail unit 5 is raised in an inoperative, stored position. The rail wheels 13 on the unit 5 are raised high enough to be out of the way during normal highway use of the vehicle and locked in this position by first locking means (not shown). When the vehicle is to be used on a railway track, the vehicle is driven to a railway crossing and maneuvered to have the road wheels of the vehicle over the rails at the crossing. The vertical moving units 50 are then moved, as shown in FIG. 4, to lower the rail unit 5 and to place the rail wheels 13 on the rails of the railway track. The vertical moving units 50 can be lowered sufficiently to raise the vehicle wheels off the track. In this case, a motor (not shown) can be provided on the rail unit 5 to drive the rail wheels and thus the vehicle. Preferably however, the vertical moving units 50 are lowered enough to have the vehicle wheels sufficiently on the track to drive the vehicle while the rail wheels maintain the vehicle on the track. Good results are obtained when a substantial portion of the weight of the vehicle, preferably about forty percent of the weight of the vehicle, is carried by the rail wheels. The rail wheels are locked in the lowered position by a second locking means (not shown). The desired vehicle weight distribution on the rail wheels is obtained when the mounting frame is initially fixed to the side rails of the vehicle. The height of the mounting frame is adjusted via the slots 28 and bolts 27 to have the vertical moving units 50 move down sufficiently to take the desired amount of vehicle weight.

In the above example the front and rear wheels of the vehicle are on the track as are the rail wheels, the weight distribution between both sets of wheels balanced so as to maintain the rail wheels on the track to guide the vehicle while having the vehicle wheels sufficiently on the track to provide power to drive the vehicle. In some cases, the vehicle may only have the front rail wheels on the track and not the vehicle front wheels because the front wheels are too wide. On trucks with dual rear wheels, the inside wheels are the ones usually placed on the track.

The axle 11 on the rail unit 5 employed with the rail wheel attachment 1 is immobile in a transverse direction with respect to the longitudinal axis of the vehicle carrying it. While this rail wheel attachment works satisfactorily, it can be difficult and time consuming at times to align the rail wheels on the attachment with the rails of the track. It is therefore preferred to have a rail unit with an axle that is movable transversely with respect to the vehicle. Such a unit will allow for easier transference of the road vehicle from the road to a railway track. A rail unit 5′ with a movable axle is shown in FIGS. 5 to 9. This rail unit 5′ has an axle 11′ with rail wheels 13′ at each end. The axle 11′ is slidably mounted in an axle frame 81. Transverse moving means, in the form of two transverse moving units 83 mounted on the axle frame 81, are connected to the axle 11′ to move the axle transversely relative to the axle frame 81.

In more detail, the axle frame 81 has a pair of side walls 85, 87 between which the axle 11′ is received as shown in FIGS. 5 and 6. The side walls 85, 87 are joined at their ends by short, top walls 89. Axle mounting means 91 are carried by the side walls 85, 87 at each end. Each mounting means 91 has a top, semicircular, inner wall 93 that opens downwardly. The top inner wall 93 is located beneath the top wall 89 and is attached thereto. The top inner walls 93 extend between top extensions 95 of the side walls 85, 87 and are attached thereto as well. The top inner wall 93 has a pair of side flanges 97 extending laterally outwardly from the bottom of the ends of the side walls 85, 87. Bottom, semicircular, outer walls 101 that open upwardly and that have a pair of side flanges 103 extending outwardly from the ends of the wall 101 are located under the top inner walls 93. The bottom outer walls 101 are attached to the top inner walls 93 via the flanges 97, 103, the walls 93, 101 together forming tubular mounting means 91 for holding the axle 11′ as will be described. The top inner wall 93 and the bottom outer wall 101, when mounted together, can carry linear bearings 105.

Attachment means 107 are provided on each end of the side walls 85, 87 of the axle frame 81. The attachment means 107 at each end comprise a pair of raised ears 109, one ear 109 on each side wall. The ears 109 extend upwardly from the top of the side walls 85, 87. A mounting hole 111 is provided at the upper, outer, end 113 of each ear 109. The axle frame 81 is located beneath the mounting frame of the mounting unit and the tubular member 75 on the bottom end 55 of the cylinder 51 of the vertical moving unit 50 on the mounting unit locates the cylinder 51 between the raised ears 109 at each end of the axle frame 81. A suitable pin 115, shown in FIG. 7, passes through the hole in the member 75 and the mounting holes 111 at the ends of the two ears 109 at each end on the axle frame 81 to lock the axle frame 81 to the mounting frame. Suitable locking means (not shown) retain the pin 115 in place.

The axle 11′ is slidably mounted in the tubular mounting means 91 on the axle frame 81 so it can move laterally of the axle frame 81. The axle 11′, as shown in FIGS. 5, 8 and 9, has two outer cylindrical sections 117, 119 joined by a central box section 121. The box section 121 has flanges 123 at both ends bolted onto flanges 125 on the inner ends of the outer sections 117, 119. The axle 11′ carries a rail wheel 13′ at each end, each rail wheel 13′ rotatably mounted on one end 127 of a spindle 129, the other end 131 of the spindle 129 fixed in the end 133 of the outer sections 117, 119 of the axle 11′.

The transverse moving means, for moving the axle 11 laterally to the longitudinal axis of a vehicle, are carried by the axle 11′ and axle frame 81. In the embodiment shown, two transverse moving units 83 are employed, one on each side of the axle 11′. The transverse moving units 83 preferably are hydraulic and each have, as shown in FIGS. 8 and 9, a hydraulic cylinder 137 formed, by part of the axle 11′ itself, near each end 133 of the axle 11′. Each cylinder 137 defines a chamber 139, closed at one end by an outer end wall 141 fixed to the cylinder 137. The other end of the chamber 139 is closed by an inner end wall 143 fixed to the cylinder 137. A piston 145 is slidably mounted in the chamber 139 with a piston rod 147, attached to the piston 145, passing out of the chamber 139 through the inner end wall 143 of the chamber into the central box section 121 of the axle 11′. The tubular end 149 of the rod 147 is attached to the approximate center of the axle frame 81 by suitable pin means 151 passing through aligned holes 153 in the frame side walls 85, 87, as shown in FIGS. 5 and 6, so as to prevent the piston 145 from moving. The pin means 151 also pass through aligned, elongated, slots 155, 157 in the side walls 159, 161 of the central box section 121 which allows the cylinder 137, and thus the axle 11′, to move relative to the piston 145.

In use, as before, the railway wheel attachment 1 is mounted on the vehicle by fixing the side plates 15, 17 of the attachment frame 7 to the beams A, B of the vehicle frame. In the non-use position, the axle 11′ is centered with respect axle frame 81, as shown in FIGS. 5 and 8, and the vertical moving units 50 are retracted with the cylinders 51, and the rail unit 5′, raised. Thus the axle frame 81, the axle 11′ and the rail wheels 13′ are raised in an inoperative, stored position. The rail unit can be locked in the inoperative, stored position by first suitable locking means (not show. The rail wheels 13′ are raised high enough to be out of the way during normal highway use of the vehicle. When the vehicle is to be used on a railway track, the vehicle is driven to a railway crossing and maneuvered to have the road wheels of the vehicle adjacent the rails at the crossing. The rail unit is unlocked and the transverse moving units 83 are then actuated to move the axle 11′ and the rail wheels 13′ sideways, as shown in FIG. 9, relative to the axle frame 81, the mounting frame 7 and the vehicle until the rail wheels 13′ are over the rails. The vertical moving units 50 are then actuated to extend to lower the axle frame 81 and thus the rail wheels 13′ onto the rails. The rail wheels 13′ are lowered enough to take up a substantial portion of the vehicle weight. Once the rail wheels 13′ are on the rails the transverse moving units 83 are moved again to move the axle frame 81, and thus the mounting frame 7 and attached vehicle, laterally to center it over the axle 11′ and the rail wheels 13′ and to place the vehicle wheels onto the tracks. The vehicle is moved when the transverse moving units 83 are actuated since the rail wheels 13′ and axle 11′ are secured in place by the rail wheel flanges 163 bearing on the sides of the track rails (not shown). It will be seen that the device is quite compact in having having the transverse moving units 83 located within the axle 11′ and under the mounting unit, and with having vertical moving units 50, to move the axle 11′ up and down relative to the mounting unit, located directly over the axle.

While the transverse moving units 83 on the rail unit have been shown as being within the axle tube, they can be located outside the tube. As shown in FIGS. 10 to 13, the axle frame of the rail unit is modified so that it can carry the cylinders of the transverse moving units outside the axle, adjacent to it, instead of within the axle. The modified axle frame 81′ of the rail unit 5″ has two main side walls 201, 203 joined by short top walls 205 at their ends as before. The main side walls 201, 203 each have a flange 207 at the bottom extending outwardly along their length. Axle retaining means 209 are mounted on the axle frame 81′ at each end. The axle retaining means 209 comprise an upper semi-circular wall 211 with projecting flanges 213 at each end and a lower semi-circular wall 215 with projecting flanges 217 at each end. The upper aid lower walls 211, 215 are clamped together about an axle, to be described, when the walls are attached via their flanges 213, 217 to the flanges 207 on the side walls 201, 203.

Projecting ears 221 are mounted at each end of the top of each side wall 201, 203. Each ear has two spaced apart mounting holes 223, 225 therein. As before, the bottom 55 of the cylinders 51 on the vertical moving units 50, are attached to the ears 221 via a pin 227 passing through the outer mounting holes 223 and through the tubular member 0.75 on the cylinder bottom 55.

The axle 231 is a plain cylinder with spindles (not shown) at its ends for mounting rail wheels 233 on the axle. The axle also carries a bracket 243 on its top, center, the bracket having two upwardly extending, spaced-apart arms 245, each with a mounting hole 247 at the top. The axle 231 is slidably mounted in the two spaced-apart axle retaining means 209 on the axle frame 81′.

The two transverse moving units 83′, in this embodiment, are mounted on top of the axle 231. The transverse moving units are preferably hydraulic and each comprise a first hydraulic cylinder 251 having a movable piston therein with a piston rod 255 extending out from one end of the cylinder. A single bracket 259, with a mounting hole 261 therein, extends from the other end of the cylinder as shown in FIG. 13. The transverse moving units 83′ include a second hydraulic cylinder 271 having a movable piston therein with a piston rod 275 extending out from one end of the cylinder. A double bracket 279, each with a mounting hole 281 therein extends from the other end of the cylinder. The first cylinder 251 has a cross-tube 287 at the end of the piston rod 255, the tube 287 sized to fit between the ears 221 at one end of the axle frame 81′ and a pin 289 passing through the inner mounting holes 225 on the ears 221 and through the tube 287 as shown in FIG. 12. The second hydraulic cylinder 271 is similarly mounted between the ears 221 on the other end of the axle frame 81′, a pin 291 passing through the inner mounting holes on the ears 221 and through a cross-tube 293 on the end of the piston rod 275. The single bracket 259 on the first cylinder 251 is positioned between the double bracket 279 on the second cylinder 271 and the brackets are located between the arms 245 of the bracket 243 on the axle tube 231. A pin 295 passes through the aligned holes 247, 261 and 281 in all the brackets, as shown in FIG. 13, to connect the cylinders 251, 271 to the axle 231. The axle 231 can be moved in either direction relative to the axle frame 81′ by the hydraulic cylinders 251, 271, the tube 231 sliding in the axle retaining means 209 relative to the axle frame 81′. The rail unit 5″, as before, can be raised or lowered along a vertical line, relative to the mounting unit, by the vertical moving means.

While the transverse moving units 83′ have been shown and described as being mounted on top of the axle 231 they could also be mounted on either side of the axle or even under the axle.

While both above attachment embodiments move the rail unit 5,5′ and 5″ along a vertical line relative to the main frame, the rail unit of the attachment could also be moved along an arc to raise or lower it. As shown in FIGS. 14 to 17, the mounting frame 7″ of the mounting unit 3″ has a sub-frame 301 rotatably attached thereto. The rail unit 5″ is attached to the sub-frame 301 for very limited vertical movement, the amount of straight-line, vertical, movement determined by the spring elements 303 mounted between the sub-frame 301 and the axle frame 81″. The mounting frame 7″ has cantilevered supports 305 extending rearwardly therefrom. The sub-frame 301 has brackets 307 extending downwardly therefrom. Swinging moving means 9″ are mounted between the cantilevered supports 305 on the mounting frame and the downwardly directed brackets 307 on the sub-frame 301 to pivot the sub-frame 301 and the attached rail unit 5″ between a raised inoperative position and a lowered operative position.

In more detail, the mounting frame 7″ has endplates 311, 313 joined by bottom support members 315. The end plates 311, 313, as before, are attached to outside of the main beams (not shown) of a vehicle with the support members 315 passing under the beams. The support members 315 carry two pair 317, 319 of cantilevered supports 305, the supports extending rearwardly of the members 315.

The sub-frame 301 comprises a tube 321 rotatably mounted in brackets 323 attached to the bottom of the end plates 311, 313. The tube 321 has vertical tubular guides 325 at each side. A support plate 327 extends inwardly from each guide 325. Two pair 333, 335 of brackets 307 extend downwardly from the tube 321. The pairs of brackets 333, 335 are aligned with the pairs 317, 319 of cantilevered supports 305.

An inner guide tube 341 extends up from each side of the axle frame 81″ into the vertical tubular guides 325. A rod 343 on the guide tube 341 projects above the closed top 345 on the tubular guide 325. A nut 347 is threaded onto the rod 343 to retain the guide tube 341 in the tubular guide 325. The spring means 303 are mounted between the bottom support plate 327 and a support 353 on the top of the axle frame 81″. The bottom of the guide tube 341 is mounted via a pin 359 which passes through the hole (not shown) at the bottom of the tube and mounting holes in the ears 361 on the top ends of the axle frame 81″ to connect the guide tube 341 to the axle frame.

The swinging moving means 9″ are connected between the free ends of the brackets 333, 335 and the free ends of the cantilevered supports 317, 319. The swinging moving means 9″ comprise a pair of swinging moving units 362, 363, one unit on each pair of brackets and associated supports. The moving units preferable are hydraulic cylinders 365, 367. The cylinders 365, 367 are pivotably connected, intermediate their ends, to the ends of supports 317, 319 by pivot pins 369. Piston rods 371, 373 extending from the cylinders 365, 367 have tubular ends 375, 377 which are connected by pivot pins 379, 381 to the brackets 333, 335. Actuation of the cylinders 365, 367 will pivot the sub-frame 301 and attached rail unit 5″ rearwardly in an arc about the axis of the tube 321 to lift the axle and attached rail wheels carried by the rail unit 5″ to a raised inoperative position.

While the rail unit of the attachment has been shown and described as being moved rearwardly, the rail unit could also be moved forwardly by having the supports 305 extend forwardly instead of rearwardly.

The swinging moving means are known. The rail wheel attachment with the known swinging moving means can use the rail unit with either the exterior transverse moving means or with interior transverse moving means.

The transverse moving means have been described with two opposed transverse moving units. However other transverse moving means, including a single transverse moving unit can be employed. While the vertical and transverse moving means have been described as being hydraulic, they could also be pneumatic, or mechanical as by a screw thread. The hydraulic connections for the vertical and transverse moving means have not been shown but it is believed that the connections would be obvious to anyone skilled in the hydraulic art.

While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, and uses and/or adaptations of the invention and following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains, and as may be applied to the central features hereinbefore set forth, and fall within the scope of the invention or limits of the claims appended hereto. 

1. A rail wheel attachment for a road vehicle allowing the road vehicle to travel on rails the attachment having a mounting unit and a rail unit underneath it; the mounting unit having a mounting frame and vertical moving means mounted on the ends of the mounting frame; the vertical moving means connected to the rail unit to raise or lower the rail unit relative to the mounting unit along a straight line; the vertical moving means having suspension means for cushioning the movement of the rail unit relative to the mounting unit.
 2. An attachment as claimed in claim 1 wherein the rail unit has an axle with rail wheels attached to the ends of the axle, the vertical moving means connected to the axle near the rail wheels.
 3. An attachment as claimed in claim 1 wherein the rail unit has an axle frame, an axle slidably mounted in the axle frame, rail wheels at the ends of the axle, transverse moving means connected between the axle and the axle frame to move the axle relative to the axle frame, the vertical moving means connected to the axle frame.
 4. An attachment as claimed in claim 3 wherein the transverse moving means are mounted within the axle.
 5. An attachment as claimed in claim 3 wherein the transverse moving means are mounted on the exterior of the axle.
 6. An attachment as claimed in claim 3 wherein the transverse moving means are mounted on top of the axle.
 7. An attachment as claimed in claim 4 wherein the transverse moving means comprise two transverse moving units mounted within the axle, each moving unit fixed at its inner end to the axle frame at about the middle of the frame.
 8. An attachment as claimed in claim 7 wherein each transverse moving unit has an end wall fixed in the axle near its outer end, a piston in the axle spaced toward the center of the axle away from the end wall, a piston rod extending from the piston to about the middle of the axle frame and connecting means connecting the end of the piston rod to the axle frame.
 9. An attachment as claimed in claim 6 wherein the transverse moving means comprise two transverse moving units mounted aligned with each other and adjacent the axle, the outer end of each moving unit connected to the axle frame, the inner end of each moving unit connected to about the center of the axle.
 10. An attachment as claimed in claim 9 wherein the axle frame has two spaced apart side walls above the axle, brackets at the end of the side walls for slidably attaching the axle frame to the axle, the transverse moving units mounted between the side walls on top of the axle.
 11. An attachment as claimed in claim 1 wherein each vertical moving means has a vertical support means mounted in a vertical position on the side of the mounting frame; the suspension means located within the vertical support means and slidable to a limited extent; a vertical moving unit slidable in the suspension means; the vertical moving unit attached at its top end to the suspension means and at its bottom end to the rail unit.
 12. An attachment as claimed in claim 3 wherein each vertical moving means has a vertical support means mounted in a vertical position on the side of the mounting frame; the suspension means located within the vertical support means and slidable to a limited extent; a vertical moving unit slidable in the suspension means; the vertical moving unit attached at its top end to the suspension means and at its bottom end to the rail unit.
 13. An attachment as claimed in claim 12 wherein the suspension means has an inner guide tube slidable to a limited extent within the vertical support means; each vertical moving unit comprises a hydraulic cylinder slidable in the inner guide tube, the hydraulic cylinder having its lower end attached to the axle frame and a piston mounted in the cylinder, a piston rod extending upwardly from the piston and attached to the inner guide tube.
 14. An attachment as claimed in claim 13 wherein the transverse moving means has a transverse moving unit on each side of the axle, each transverse moving unit having an end wall fixed in the axle near its outer end, a piston in the axle spaced toward the center of the axle away from the end wall, a piston rod extending from the piston to about the middle of the axle support frame, and connecting means connecting the end of the piston rod to the axle frame.
 15. An attachment as claimed in claim 3 wherein the transverse moving means has a transverse moving unit on each side of the axle, each transverse moving unit having an end wall fixed in the axle near its outer end, a piston in the axle spaced toward the center of the axle away from the end wall, a piston rod extending from the piston to about the middle of the axle support frame, and connecting means connecting the end of the piston rod to the axle frame.
 16. Amounting unit for use in a rail wheel attachment, the mounting unit having: a mounting frame; vertical moving means mounted at the sides of the mounting frame, each vertical moving means comprising: vertical support means on the mounting frame; suspension means mounted within the support means and slidable to a limited extent, the suspension means having spring means connected to the support means; and a vertical moving unit slidable in each suspension means, the vertical moving unit connected at its top end to the suspension means and having attaching means at its bottom end for attaching to a rail unit.
 17. A mounting unit as claimed in claim 16 wherein the vertical support means comprises a vertical, open-ended mounting tube; the suspension means having a inner guide tube with an open bottom end and a top cover, and spring means, the spring means connected between the mounting tube and the guide tube to cushion movement of the rail unit relative to the mounting frame; the vertical moving unit comprising: a hydraulic cylinder slidable in the guide tube having the attaching means on its lower end attachable to the rail unit, a piston mounted in the cylinder, and a piston rod extending upwardly from the piston and passing through the hydraulic cylinder to be attached to the top of the guide tube.
 18. A mounting unit as claimed in claim 17 wherein guide tube has a cover at its top end for abutting against the top of the mounting tube to help retain the guide tube within the mounting tube, the piston rod attached to the cover.
 19. A mounting unit as claimed in claim 17 wherein the mounting tube has a bottom support plate near its bottom end, the support plate extending to either side of the mounting tube; the guide tube having a mounting plate near its bottom end, the mounting plate extending to either side of the guide tube and located below the support plate; the spring means comprising a spring member on each side of the mounting tube, each spring member mounted between the bottom support plate on the mounting tube and the mounting plate on the guide tube.
 20. A rail unit for use in a rail wheel attachment, the rail unit having an axle frame, an axle slidably mounted on the axle frame with wheels at the ends of the axle, and transverse moving means on the axle frame connecting the axle frame to the axle.
 21. A rail unit as claimed in claim 20 wherein the transverse moving means are mounted within the axle.
 22. A rail unit as claimed in claim 20 wherein the transverse moving means are mounted on the exterior of the axle.
 23. A rail unit as claimed in claim 21 wherein the transverse moving means comprise two moving units mounted within the axle, each moving unit fixed at its inner end to the axle frame at about the middle of the frame.
 24. A rail unit as claimed in claim 23 wherein each transverse moving unit has an end wall fixed in the axle near its outer end, a piston in the axle spaced toward the center of the axle away from the end wall, a piston rod extending from the piston to about the middle of the axle support frame, and connecting means connecting the end of the piston rod to the axle frame.
 25. A rail unit as claimed in claim 22 wherein the transverse moving means comprise two moving units mounted aligned with each other and adjacent the axle, the outer end of each moving unit connected to the axle frame, the inner end of each moving unit connected to about the center of the axle.
 26. A rail unit as claimed in claim 25 wherein the axle frame has two spaced apart side walls above the axle, brackets at the end of the side walls for slidably attaching the axle frame to the axle, the vertical moving units mounted: between the side walls on top of the axle.
 27. A rail wheel attachment for a road vehicle allowing the road vehicle to travel on rails, the attachment having a mounting unit and a rail unit underneath it; the mounting unit having a mounting frame and vertical moving means mounted on the ends of the mounting frame; the rail unit having an axle frame, an axle slidably mounted in the axle frame, rail wheels at the ends of the axle, transverse moving means connected between the axle and the axle frame, the vertical moving means connected to the axle frame to raise or lower the rail unit relative to the mounting unit along a straight line.
 28. An attachment as claimed in claim 27 wherein the transverse moving means are mounted within the axle.
 29. An attachment as claimed in claim 27 wherein the transverse moving means are mounted on the exterior of the axle.
 30. An attachment as claimed in claim 27 wherein each vertical moving means has a vertical support means on the side of the mounting frame; a suspension means mounted on the support means and movable to a limited extent; and a vertical moving unit, the vertical moving unit slidable in the suspension means, the vertical moving unit attached at its bottom end to the rail unit.
 31. An attachment as claimed in claim 30 wherein each vertical moving unit comprises a hydraulic cylinder slidable in the suspension means and having its lower end attached to the axle frame, a piston mounted in the cylinder, and a piston rod extending upwardly from the piston and attached to the suspension means.
 32. Vertical moving means for use in a rail wheel attachment having a mounting unit and a rail unit, the vertical moving means connecting the rail unit to the mounting unit for movement vertically relative to the mounting unit; the vertical moving means comprising: vertical support means for mounting on the side of the mounting frame; suspension means slidable to a limited extent within the support means; and a vertical moving unit mounted within the suspension means, the vertical moving unit having attaching means at its bottom end for attaching to the rail unit and connecting means at its top end for connecting to the top of the suspension means.
 33. Vertical moving means as claimed in claim 32 wherein the vertical support means comprising a vertical, open-ended mounting tube; the suspension means has a guide tube slidable to a limited extent in the open-ended tube, the vertical moving unit having a hydraulic cylinder slidable in the guide tube, the lower end of the cylinder carrying the attaching means, a piston mounted in the cylinder, and a piston rod extending upwardly from the piston and passing through the hydraulic cylinder to be attached to the top of the guide tube.
 34. Vertical moving means as claimed in claim 33 wherein the guide tube has a cover at its top end for abutting against the top of the vertical support means to retain the guide tube within the support means, the piston rod attached to the cover.
 35. Vertical moving means as claimed in claim 33 wherein the mounting tube has a bottom support plate near its bottom end, the support plate extending to either side of the tube; the guide tube having a mounting plate near its bottom end, the mounting plate extending to either side of the sleeve and located below the support plate, the mounting plate and support plate adapted to receive spring means, forming part of the suspension means, there between.
 36. A method of placing a vehicle carrying a rail wheel attachment on a railway track, the attachment having a frame attachable to the vehicle, the frame carrying a rail unit with rail wheels, the attachment having moving means for raising and lowering the rail unit relative to the frame and transverse moving means for moving the rail unit laterally with respect to the frame, the method comprising the steps of: positioning the vehicle with its tires adjacent the rails of the track, moving the rail wheels on the attachment laterally over the rails, lowering the rail wheels onto the rails sufficiently to transfer a major portion of the weight of the vehicle onto the rail wheels from the vehicle wheels and then moving the vehicle laterally with respect to the rail wheels to position the vehicle wheels on the rails.
 37. A method as claimed in claim 36 wherein about forty percent of the vehicle weight is placed on the rail wheels. 